IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.2.178.128/25

network10.2.178.128/25

broadcast10.2.178.255

first host10.2.178.129

last host10.2.178.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.178.128/25

address00001010.00000010.10110010.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.10110010.10000000

broadcast00001010.00000010.10110010.11111111

green = network part, grey = host part

hex0x0a02b280

decimal167948928

reverse dns128.178.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:b280

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.178.128/32	10.2.178.128 – 10.2.178.128	10.2.178.128
2	10.2.178.129/32	10.2.178.129 – 10.2.178.129	10.2.178.129
3	10.2.178.130/32	10.2.178.130 – 10.2.178.130	10.2.178.130
4	10.2.178.131/32	10.2.178.131 – 10.2.178.131	10.2.178.131
5	10.2.178.132/32	10.2.178.132 – 10.2.178.132	10.2.178.132
6	10.2.178.133/32	10.2.178.133 – 10.2.178.133	10.2.178.133
7	10.2.178.134/32	10.2.178.134 – 10.2.178.134	10.2.178.134
8	10.2.178.135/32	10.2.178.135 – 10.2.178.135	10.2.178.135
9	10.2.178.136/32	10.2.178.136 – 10.2.178.136	10.2.178.136
10	10.2.178.137/32	10.2.178.137 – 10.2.178.137	10.2.178.137
11	10.2.178.138/32	10.2.178.138 – 10.2.178.138	10.2.178.138
12	10.2.178.139/32	10.2.178.139 – 10.2.178.139	10.2.178.139
13	10.2.178.140/32	10.2.178.140 – 10.2.178.140	10.2.178.140
14	10.2.178.141/32	10.2.178.141 – 10.2.178.141	10.2.178.141
15	10.2.178.142/32	10.2.178.142 – 10.2.178.142	10.2.178.142
16	10.2.178.143/32	10.2.178.143 – 10.2.178.143	10.2.178.143
17	10.2.178.144/32	10.2.178.144 – 10.2.178.144	10.2.178.144
18	10.2.178.145/32	10.2.178.145 – 10.2.178.145	10.2.178.145
19	10.2.178.146/32	10.2.178.146 – 10.2.178.146	10.2.178.146
20	10.2.178.147/32	10.2.178.147 – 10.2.178.147	10.2.178.147
21	10.2.178.148/32	10.2.178.148 – 10.2.178.148	10.2.178.148
22	10.2.178.149/32	10.2.178.149 – 10.2.178.149	10.2.178.149
23	10.2.178.150/32	10.2.178.150 – 10.2.178.150	10.2.178.150
24	10.2.178.151/32	10.2.178.151 – 10.2.178.151	10.2.178.151
25	10.2.178.152/32	10.2.178.152 – 10.2.178.152	10.2.178.152
26	10.2.178.153/32	10.2.178.153 – 10.2.178.153	10.2.178.153
27	10.2.178.154/32	10.2.178.154 – 10.2.178.154	10.2.178.154
28	10.2.178.155/32	10.2.178.155 – 10.2.178.155	10.2.178.155
29	10.2.178.156/32	10.2.178.156 – 10.2.178.156	10.2.178.156
30	10.2.178.157/32	10.2.178.157 – 10.2.178.157	10.2.178.157
31	10.2.178.158/32	10.2.178.158 – 10.2.178.158	10.2.178.158
32	10.2.178.159/32	10.2.178.159 – 10.2.178.159	10.2.178.159
33	10.2.178.160/32	10.2.178.160 – 10.2.178.160	10.2.178.160
34	10.2.178.161/32	10.2.178.161 – 10.2.178.161	10.2.178.161
35	10.2.178.162/32	10.2.178.162 – 10.2.178.162	10.2.178.162
36	10.2.178.163/32	10.2.178.163 – 10.2.178.163	10.2.178.163
37	10.2.178.164/32	10.2.178.164 – 10.2.178.164	10.2.178.164
38	10.2.178.165/32	10.2.178.165 – 10.2.178.165	10.2.178.165
39	10.2.178.166/32	10.2.178.166 – 10.2.178.166	10.2.178.166
40	10.2.178.167/32	10.2.178.167 – 10.2.178.167	10.2.178.167
41	10.2.178.168/32	10.2.178.168 – 10.2.178.168	10.2.178.168
42	10.2.178.169/32	10.2.178.169 – 10.2.178.169	10.2.178.169
43	10.2.178.170/32	10.2.178.170 – 10.2.178.170	10.2.178.170
44	10.2.178.171/32	10.2.178.171 – 10.2.178.171	10.2.178.171
45	10.2.178.172/32	10.2.178.172 – 10.2.178.172	10.2.178.172
46	10.2.178.173/32	10.2.178.173 – 10.2.178.173	10.2.178.173
47	10.2.178.174/32	10.2.178.174 – 10.2.178.174	10.2.178.174
48	10.2.178.175/32	10.2.178.175 – 10.2.178.175	10.2.178.175
49	10.2.178.176/32	10.2.178.176 – 10.2.178.176	10.2.178.176
50	10.2.178.177/32	10.2.178.177 – 10.2.178.177	10.2.178.177
51	10.2.178.178/32	10.2.178.178 – 10.2.178.178	10.2.178.178
52	10.2.178.179/32	10.2.178.179 – 10.2.178.179	10.2.178.179
53	10.2.178.180/32	10.2.178.180 – 10.2.178.180	10.2.178.180
54	10.2.178.181/32	10.2.178.181 – 10.2.178.181	10.2.178.181
55	10.2.178.182/32	10.2.178.182 – 10.2.178.182	10.2.178.182
56	10.2.178.183/32	10.2.178.183 – 10.2.178.183	10.2.178.183
57	10.2.178.184/32	10.2.178.184 – 10.2.178.184	10.2.178.184
58	10.2.178.185/32	10.2.178.185 – 10.2.178.185	10.2.178.185
59	10.2.178.186/32	10.2.178.186 – 10.2.178.186	10.2.178.186
60	10.2.178.187/32	10.2.178.187 – 10.2.178.187	10.2.178.187
61	10.2.178.188/32	10.2.178.188 – 10.2.178.188	10.2.178.188
62	10.2.178.189/32	10.2.178.189 – 10.2.178.189	10.2.178.189
63	10.2.178.190/32	10.2.178.190 – 10.2.178.190	10.2.178.190
64	10.2.178.191/32	10.2.178.191 – 10.2.178.191	10.2.178.191
65	10.2.178.192/32	10.2.178.192 – 10.2.178.192	10.2.178.192
66	10.2.178.193/32	10.2.178.193 – 10.2.178.193	10.2.178.193
67	10.2.178.194/32	10.2.178.194 – 10.2.178.194	10.2.178.194
68	10.2.178.195/32	10.2.178.195 – 10.2.178.195	10.2.178.195
69	10.2.178.196/32	10.2.178.196 – 10.2.178.196	10.2.178.196
70	10.2.178.197/32	10.2.178.197 – 10.2.178.197	10.2.178.197
71	10.2.178.198/32	10.2.178.198 – 10.2.178.198	10.2.178.198
72	10.2.178.199/32	10.2.178.199 – 10.2.178.199	10.2.178.199
73	10.2.178.200/32	10.2.178.200 – 10.2.178.200	10.2.178.200
74	10.2.178.201/32	10.2.178.201 – 10.2.178.201	10.2.178.201
75	10.2.178.202/32	10.2.178.202 – 10.2.178.202	10.2.178.202
76	10.2.178.203/32	10.2.178.203 – 10.2.178.203	10.2.178.203
77	10.2.178.204/32	10.2.178.204 – 10.2.178.204	10.2.178.204
78	10.2.178.205/32	10.2.178.205 – 10.2.178.205	10.2.178.205
79	10.2.178.206/32	10.2.178.206 – 10.2.178.206	10.2.178.206
80	10.2.178.207/32	10.2.178.207 – 10.2.178.207	10.2.178.207
81	10.2.178.208/32	10.2.178.208 – 10.2.178.208	10.2.178.208
82	10.2.178.209/32	10.2.178.209 – 10.2.178.209	10.2.178.209
83	10.2.178.210/32	10.2.178.210 – 10.2.178.210	10.2.178.210
84	10.2.178.211/32	10.2.178.211 – 10.2.178.211	10.2.178.211
85	10.2.178.212/32	10.2.178.212 – 10.2.178.212	10.2.178.212
86	10.2.178.213/32	10.2.178.213 – 10.2.178.213	10.2.178.213
87	10.2.178.214/32	10.2.178.214 – 10.2.178.214	10.2.178.214
88	10.2.178.215/32	10.2.178.215 – 10.2.178.215	10.2.178.215
89	10.2.178.216/32	10.2.178.216 – 10.2.178.216	10.2.178.216
90	10.2.178.217/32	10.2.178.217 – 10.2.178.217	10.2.178.217
91	10.2.178.218/32	10.2.178.218 – 10.2.178.218	10.2.178.218
92	10.2.178.219/32	10.2.178.219 – 10.2.178.219	10.2.178.219
93	10.2.178.220/32	10.2.178.220 – 10.2.178.220	10.2.178.220
94	10.2.178.221/32	10.2.178.221 – 10.2.178.221	10.2.178.221
95	10.2.178.222/32	10.2.178.222 – 10.2.178.222	10.2.178.222
96	10.2.178.223/32	10.2.178.223 – 10.2.178.223	10.2.178.223
97	10.2.178.224/32	10.2.178.224 – 10.2.178.224	10.2.178.224
98	10.2.178.225/32	10.2.178.225 – 10.2.178.225	10.2.178.225
99	10.2.178.226/32	10.2.178.226 – 10.2.178.226	10.2.178.226
100	10.2.178.227/32	10.2.178.227 – 10.2.178.227	10.2.178.227
101	10.2.178.228/32	10.2.178.228 – 10.2.178.228	10.2.178.228
102	10.2.178.229/32	10.2.178.229 – 10.2.178.229	10.2.178.229
103	10.2.178.230/32	10.2.178.230 – 10.2.178.230	10.2.178.230
104	10.2.178.231/32	10.2.178.231 – 10.2.178.231	10.2.178.231
105	10.2.178.232/32	10.2.178.232 – 10.2.178.232	10.2.178.232
106	10.2.178.233/32	10.2.178.233 – 10.2.178.233	10.2.178.233
107	10.2.178.234/32	10.2.178.234 – 10.2.178.234	10.2.178.234
108	10.2.178.235/32	10.2.178.235 – 10.2.178.235	10.2.178.235
109	10.2.178.236/32	10.2.178.236 – 10.2.178.236	10.2.178.236
110	10.2.178.237/32	10.2.178.237 – 10.2.178.237	10.2.178.237
111	10.2.178.238/32	10.2.178.238 – 10.2.178.238	10.2.178.238
112	10.2.178.239/32	10.2.178.239 – 10.2.178.239	10.2.178.239
113	10.2.178.240/32	10.2.178.240 – 10.2.178.240	10.2.178.240
114	10.2.178.241/32	10.2.178.241 – 10.2.178.241	10.2.178.241
115	10.2.178.242/32	10.2.178.242 – 10.2.178.242	10.2.178.242
116	10.2.178.243/32	10.2.178.243 – 10.2.178.243	10.2.178.243
117	10.2.178.244/32	10.2.178.244 – 10.2.178.244	10.2.178.244
118	10.2.178.245/32	10.2.178.245 – 10.2.178.245	10.2.178.245
119	10.2.178.246/32	10.2.178.246 – 10.2.178.246	10.2.178.246
120	10.2.178.247/32	10.2.178.247 – 10.2.178.247	10.2.178.247
121	10.2.178.248/32	10.2.178.248 – 10.2.178.248	10.2.178.248
122	10.2.178.249/32	10.2.178.249 – 10.2.178.249	10.2.178.249
123	10.2.178.250/32	10.2.178.250 – 10.2.178.250	10.2.178.250
124	10.2.178.251/32	10.2.178.251 – 10.2.178.251	10.2.178.251
125	10.2.178.252/32	10.2.178.252 – 10.2.178.252	10.2.178.252
126	10.2.178.253/32	10.2.178.253 – 10.2.178.253	10.2.178.253
127	10.2.178.254/32	10.2.178.254 – 10.2.178.254	10.2.178.254
128	10.2.178.255/32	10.2.178.255 – 10.2.178.255	10.2.178.255

01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefix	subnet mask	addresses	hosts	in your /25
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	-
/22	255.255.252.0	1,024	1,022	-
/23	255.255.254.0	512	510	-
/24	255.255.255.0	256	254	-
/25	255.255.255.128	128	126	1
/26	255.255.255.192	64	62	2 split →
/27	255.255.255.224	32	30	4 split →
/28	255.255.255.240	16	14	8 split →
/29	255.255.255.248	8	6	16 split →
/30	255.255.255.252	4	2	32 split →
/31	255.255.255.254	2	2	64 split →
/32	255.255.255.255	1	1	128 split →

02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →